HER2 Support Group Forums - View Single Post - More info on Bayer test from Dr. Carney (Walt)

MGordon · 07-07-2005, 10:19 PM

Tricia -

I'll hope to shed a little light on your confusion. Please remember, I am not a doctor and I will be relaying my understanding - I do not mean to speak for Dr. Carney. I also talk alot, so try to be patient with me! ;-)

The FISH and/or IHC test is a tissue based test. That means a surgeon has to perform a biopsy to take the tissue to run these tests against. Usually the primary cancer is sampled from a biopsy or removed during the lumpectomy and one of these tests (among many others) is run using the tissue from the tumor which determines the HER2 status, as well as several other important markers (diplodomy comes to mind).

Generally, as a course of treatment is performed there is no follow-on biopsy - and in many cases there is nothing left to biopsy - so the only tissue available is from the original biopsy or lumpectomy. In the cases where the disease metastisizes there may be another biopsy. In Lisa's case, she recurred to the liver, bones and brain. A liver biopsy was performed, and since there was "new" tissue available from this biopsy, the onc's could run a new series of FISH and/or IHC tests for issues like HER2 status.

The Bayer-Serum test is a diagnostic tool that the doc's can run via blood samples instead of biopsy. By looking for specific markers in the blood (I am going to refer you to the wonderful slide show that Dr. Carney put together and is listed in previous posts) based on his research showing how HER2 is shed into the blood stream. If an onc really wanted to, they could now test a patients HER2 status with every blood test and not require additional biopsies to determine a change in HER2 status. I do not believe that the Bayer-Serum test will replace the FISH/IHC tests performed on tissue samples, but will enhance monitoring and detection without the requirement of additional tissue removal.

The goal is to be able to more closely monitor any change in status without requiring any invasive surgery - because even a biopsy is invasive. If your course of treatment has been anything like Lisa's - blood draw needles are seen every week! And although some of us might dislike needles, they sure beat invasive biopsy and/or surgery.

I would tend to agree with you that FISH and IHC were not performed on your original tumor. I cannot say with all certainty, but at least the general acceptance and availability of these tests is not over 20 years old. Just curious here, with your lung recurrance, did you have a biopsy recently or did the onc test your 14 year old lung tumor sample? Most tumors are frozen and kept over a long period of time.

Regardless, I would agree with your understanding that HER2 status makes for an agressive, fast-acting cancer. And yes, Herceptin is currently the best course of treatment to slow down this aggressiveness. As far as how you survived without it - because you are who you are.

I believe that people and faith and attitude defeat cancer and drugs like Herceptin are only a tool to help. I would guess that you are a strong woman and your attitude rocks! Thank God for drugs like Herceptin and Drs. like Dr. Black and Dr. Love and Dr. Moran (he's our Onc)- and of course Dr. Slamon. But the real heroes in the battle are you and those like you (and of course my Lisa!).

I really hope this helped at least a little...

Love and Light
Mel (Spouse of Lisa)

07-07-2005, 10:19 PM	#3
MGordon Senior Member Join Date: Nov 2004 Location: Colorado Posts: 131	Tricia - I'll hope to shed a little light on your confusion. Please remember, I am not a doctor and I will be relaying my understanding - I do not mean to speak for Dr. Carney. I also talk alot, so try to be patient with me! ;-) The FISH and/or IHC test is a tissue based test. That means a surgeon has to perform a biopsy to take the tissue to run these tests against. Usually the primary cancer is sampled from a biopsy or removed during the lumpectomy and one of these tests (among many others) is run using the tissue from the tumor which determines the HER2 status, as well as several other important markers (diplodomy comes to mind). Generally, as a course of treatment is performed there is no follow-on biopsy - and in many cases there is nothing left to biopsy - so the only tissue available is from the original biopsy or lumpectomy. In the cases where the disease metastisizes there may be another biopsy. In Lisa's case, she recurred to the liver, bones and brain. A liver biopsy was performed, and since there was "new" tissue available from this biopsy, the onc's could run a new series of FISH and/or IHC tests for issues like HER2 status. The Bayer-Serum test is a diagnostic tool that the doc's can run via blood samples instead of biopsy. By looking for specific markers in the blood (I am going to refer you to the wonderful slide show that Dr. Carney put together and is listed in previous posts) based on his research showing how HER2 is shed into the blood stream. If an onc really wanted to, they could now test a patients HER2 status with every blood test and not require additional biopsies to determine a change in HER2 status. I do not believe that the Bayer-Serum test will replace the FISH/IHC tests performed on tissue samples, but will enhance monitoring and detection without the requirement of additional tissue removal. The goal is to be able to more closely monitor any change in status without requiring any invasive surgery - because even a biopsy is invasive. If your course of treatment has been anything like Lisa's - blood draw needles are seen every week! And although some of us might dislike needles, they sure beat invasive biopsy and/or surgery. I would tend to agree with you that FISH and IHC were not performed on your original tumor. I cannot say with all certainty, but at least the general acceptance and availability of these tests is not over 20 years old. Just curious here, with your lung recurrance, did you have a biopsy recently or did the onc test your 14 year old lung tumor sample? Most tumors are frozen and kept over a long period of time. Regardless, I would agree with your understanding that HER2 status makes for an agressive, fast-acting cancer. And yes, Herceptin is currently the best course of treatment to slow down this aggressiveness. As far as how you survived without it - because you are who you are. I believe that people and faith and attitude defeat cancer and drugs like Herceptin are only a tool to help. I would guess that you are a strong woman and your attitude rocks! Thank God for drugs like Herceptin and Drs. like Dr. Black and Dr. Love and Dr. Moran (he's our Onc)- and of course Dr. Slamon. But the real heroes in the battle are you and those like you (and of course my Lisa!). I really hope this helped at least a little... Love and Light Mel (Spouse of Lisa)